Skip to main content
It looks like you're using Internet Explorer 11 or older. This website works best with modern browsers such as the latest versions of Chrome, Firefox, Safari, and Edge. If you continue with this browser, you may see unexpected results.
The International Standard Book Number (ISBN) is a unique numeric commercial book identifier.
An ISBN is assigned to each edition and variation (except reprintings) of a book. For example, an ebook, a paperback, and a hardcover edition of the same book would each have a different ISBN. The ISBN is 13 digits long if assigned on or after 1 January 2007, and 10 digits long if assigned before 2007.
Occasionally, a book may appear without a printed ISBN if it is printed privately or the author does not follow the usual ISBN procedure; however, this can be rectified later.
Request a New ISBN
As a service to the Caltech community, the Caltech Library provides ISBNs for self-published materials.
If you are interested in obtaining an ISBN for your self-published book, please contact the Library.
Information Needed for Assigning ISBNs
Before requesting an ISBN for your book, please gather the following information. The library will ask you to include it in an email.
- Author(s)’ names and or contributors(s) name(s)
- Title and subtitle for set ( and each volume title if different)
- Subject of title (up to 2)
- Edition information
- Volume information (number of volumes, volume number of each title if different)
- Illustrations in book?
- Formats in which book will appear – each format gets own ISBN: paperback, hardback, ebook
- Type of binding (paperback or hardback) for each
- Where book will be sold
- Publication date
- Price information
- Target audience
- Cover image if available - JPG format is best.